Induction-motor-controlling apparatus.



A. SUNDHB INDUCTION MOTOR CONTROLLING APPARATUS. APPLICATION FILEDHOV.16, 1905.

1,002,336. Ementmi Sept. 5, 1911.

20 5/ WITNESSES:

' 'e, zgo z INVENTOR ATTORNEY "UNITED STATES PATENT OFFICE.

AUGUST SUNDIL'OF YONKERS, NEW YORK OF JERSEY CITY NEW JERSEY,

ASSIGNOB TO OTIS ELEVATOR COMPANY, A CORPORATION OF NEW JERSEY.

INDUOTION-MO'IOR-CONTROLLING APPARATUS.

Specification of Letters Patent.

Patented Sept. 5, 1911.

Application filed November 18. 1805. Serial No. 287,762.

Be it known that I, AUGUST SUNDH, a citizen of the United States,residing at Yonkers," in the county of Westchester and State of NewYork, have invented a new and useful Improvement inInduction-Motor-Controlling Apparatus, of which the following is aspecification.

My invention relates to motor cont-rolling apparatus, and is hereinshown applied to an elevator system, but it is not so limited, as it mayhave a general application.

()ne of the objects of1my invention is the provision of simple andefficient means for starting, operating, and'stopping an electric motor.

A further object of my invention is the provision of a mechanical. brakeconnected to the motor, and operated thereby in proportion to the speedthereof. A further object of the present invention,

- is the provision of means for operating a starting device for anelectric motor in portion tothe speed thereof.

More particularly it is the object of the present .invention, to providean electromechanical brake device for a motor, and combine such devicewith a motor starting device, both of such devices to be operated inproportion to the speed of the motor.

Other objects of the invention will appear hereinafter, the novelcombinations of ele ments being pointed out 'in the claims at the end'ofthis specification.

In the single figure of the drawing, an elevator hoisting apparatus .His shown, for operating the car C, inwhich is located the manual switchS for controlling the reversing switches R R, which in turn control thecircuits to the elevator motor M. As will be seen, this motor isconnected by a shaft 7 6 to the hoisting apparatus H. This hoistingapparatus may be of any desired type, but the drum type is shown since Ideemit preferable. So far as my invention,

pro-

- hereinafter described, is concerned, the moa, b, 0, designate themains which are connected'between some suitable source of alternatingcurrent supply, and a transformer T.

L designates a three pole main line switch.

When the lever 13 in the car C is moved into engagement with the rigidlyfixed con tact strip 14, a single phase circuit is closed from the wirea to andthrongh the wire 12, lever 13, contact strip 14, wire 16, coil 2of reversing switch R, wire 9, and thence to wire I). The coil orsolenoid 2 will therefore be excited by the single phase current andlift its core 4 so as to movethe insulated contacts 8 and 7' carriedthereby into engagement with the fixed contacts 5' and 6. This will havethe effect of closing the circuits to the motor M, which may be tracedas follows: From the conductor a,

moved into engagement with the contact strip 15, a single phase circuitis closed from Wire a through wire 12, lever 13,

contact 15, Wire 17, coil 2, wires 1 and 9, to wire.b. In this case thecoil 2 will be excited with a single phase current and consequently itscore 4 lifted so as to bring the insulated contacts 7 and 8 intoengagement with the fixed contacts 5 and 6 respectively. This willresult in the'reversal of the connections of the conductors a and c tothe motor terminals 21 and 20, and therefore also a reversal of therotation of the motor M.

It should be noted that I have herein shown laminated the frames 3 and 3of the reversing switch electro-magnets, and I have also shownt-hecores. 4 and 4' laminated so that these" electro-magnets will beoperated more efliciently by alternating currents. It is to beunderstood, however, that when a direct current motor is used fordriving the elevator apparatus, I may use solid electro-magnet framesand cores if desired.

Connected across two of the conductors leading from the alternatingcurrent source of supply, I have shown a solenoid 24. In this instancethis solenoid is connected between the phase wire 6 and the wire 18, by

' against t connected to the motor shaft 76.

means of the leads 22 and 23. The solenoid 24 when excited by singlephase current, will move its core 26 to the right and thereby releasethe brake shoe B, which is connected to said core 26 preferably by a rodWhen the current through the coil 24 is cut off or interrupted,thespring 28 in the casin' 29 acts to apply the brake shoe B %e brakepulley P, which is rigidly adjusting screw 32 which is at the right ofder 43 is moved to its upper adapted to said spring.

The magnetframe, which is herein shown laminated so as to adapt thebrake magnet to alternating currents, is placed between the casing 29and an additional casing 35. It will be noticed that each of thesecasings is cylindrical in form, and that the piston 30 is adapted tomove in the casing 29, and an additional piston 34 is adapted to move inthe cylinder 35. The piston 34 is connected by a rod 33 to the core 26,so as to move therewith. The piston 34 is in reality a valve providedwith circumferential grooves 36 and 38, and with pistons 39 and 40. Ahole 37 extends from the right-hand end of the piston 34 to the groove36, into which it opens at 37. A pipe 77 establishes communicationbetween the cylinder 35 and the cylinder or casing 29. When the elevatorcar is at rest and the brake applied, the pipe 77 establishescommunication between the groove 36 andthe casing 29 to the right of thebrake piston 30. A port 41 is shown in the casing 35, opposite thegroove 38, and the pipe 42 extends be tween the casing 35 opposite saidgroove and the cylinder 43. v

The cylinder 43 is arranged vertically, but may be placed in any otherdesired position, as it does not depend upon gravity for its operationbut may, however, by inverting the cylinder 43. A piston 44 in thiscylinposition by a spring 48, and is moved downwardly against the actionof said spring by means of the fluid pressure apparatus A, hereinafterdescribed. The port 47 allows free movement to the piston 44; a'stem orred 45 connects the piston 44 to the bridge piece 46. which, when moveddownwardly, is connect the fixed contacts 51 and 5 2, 57 and 58, etc.,to cut out step-by-step, the starting resistance 78. This startingresistance may be delta connected as shown,

minals are connected by the leads 63, 64,-

and 66, respectively, to the slip rung-s 79, 80, and 81 of the rotor ofthe motor M. If the bridge piece 46 is moved downwardly so as to connectthe contacts 51 and 52, it will be readily seen that the sections 55 and56 will be short-circuited, since a wire 49 connects the terminal 50 tothe bridge piece 46. The terminal 50 now in effect, includes the points53 and 54, and bridge piece 46. Upon further downward movement of thebridge piece 46, the successive sections of the resistance 78 are cutout, and finally when the contacts 59 and 60 are electrically connected,all the sections, including that ,designated 67, are cut out and themotor may attain its maximum speed.

Some suitable fluid pressure apparatus A is connected to be driven bythe motor M, and to produce the pressure in proportion to the speed ofsaid motor. To illustrate the principle of my invention, 1 have hereinshown an air pump adapted to be driven by eccentrics mounted on themotor shaft 76. The straps E, E, of said eccentrics are respectivelyconnected by the eccentric rods 74 and 75 to the pistons 72 and 73,which areadapted to play alternately in the cylinders 70 and 71, and bymeans of suitable controlling, spring-pressed puppet valves, air ispumped from the atmosphere into the chamber 69 and thence forced throughthe pipe 68 into the cylinder 35 to the right of the piston 40. When thebrake electro-magnet is deenergized, the fluid forced hrough the pi e 68will con tinue through the passage 3 to the groove 36 and thence by wayof pipe 77 into the casing 28 to the right of the piston 30. Preferably,the chamber in which the spring 28 is located is air tight, so as toincrease the eiiiciency of the fluid pressure apparatus when moving thepiston 30 to the left to increase the braking action on the brake pulicy 1?. When, however, the brake magnet is energized, its core 26 willbe drawn to the right against the action of the spring 28 to release thebrake shoe B. At the same time the piston 34 is moved to the right, sothat the left hand portion of said piston will open communicationbetween the cylinder 29 and the atmosphere through the pipe 77 and theaperture 78. The apparatus is so constructed that when the core 26 isthus moved to the right, the groove 36 will be placed over the pipe 42so that communication-is established bet-ween the pipe 68 and thecylinder 43 above the piston 44 or below it if the s' ring 48 isomitted. The car switch having 8 operating positions, and the brakemagnet then energized to release the brake shoe B, and one of thereversing switches R or R having been necessarily also operated, the

is preferably so designed, that the motor current will fiow through themotor stator to tend to rotate said motor to move the car in the desireddirection. The resistance 78 M will now rotate at slow speed, whereuponthe fluid pressure apparatus, which is herein shown as an air pump,willbe operated to roduce fluid pressure on the up per side 0? thepiston 44. The bridge piece 46 will consequently begin to descend or bemoved into engagement with the fixedcontacts connected to the startingresistance. A certain interval dependent upon the load to be driven mustela se, however, after the motor is started, beflhre, sufiicientpressure is brought to bear on the piston 44 to move the samejso thatthe bridge piece 46 will electrically connect the contacts -51 and 52.When this occurs, more current will flow through the stator circuits,and consequently the speed of'the motor will be increased. This willhave the effect of increasing the speed of operation of the fluidpressure apparatus to move the piston 44 downwardly a greatendistance toeffect the short circuiting of additional sections of the startingresistance. This action continues until the motor has been acceleratedgradually to full speed in a predetermined time with any given load, andthe bridge piece 46 connects the contact strips 59 and 60. As

the piston 44 is moved downwardly, the reaction of the spring 48 isgradually increased sothat greater fluid pressure is required to givethe piston 44 a further movement. TlllS is taken care of, however, bythe gradually increased rapidity of action of the fluid pressureapparatus A, due to the gradual acceleration of the motor M. The

eflect thereof will be a substantially uniform movement of the bridgepiece 46 downwardly over the contact strips which it' successivelyconnects. The bridge piece 46 is of suflicient thickness or width toengage a lower set of contacts before it leaves an upper set.

Var1ous changes may be made in the de-' .tails and arrangement of partsby those skilled in the art, without departing from the spirit and scopeof my invention.

It will be noticed that after the piston 44 has been moved to itslowermost position, so as to effect the connection of the strips 59 and60 by the bridge piece 46, the fluid pressure apparatus continues toexert a fluid pressure on the upper side of the piston 44 and thus holdsthe bridge piece 46 in its lowermost position. In order not to let thisa pressure become too 7 may fit loosely in the cylinder 43 so that eenmoved to one of the tain distance below 'matically regulated great, thepiston 44 the fiuid at very high pressure, may escape to the under sideof said piston and through the aperture 47 to the atmosphere, or theapprture 47 may occupy such a position that w en too great a pressure isexerted on the piston 44, said piston will be moved a cersaid apertureto open the same, to a certain extent to allow the fluid to escape fromabove said piston through said aperture 47 to the atmosphere. This willhave the effect of regulatin the maximum pressure on the upper si e ofsaid piston. It should be further noted, however, that if the motor M isslowed down through any cause, as-by meansof a heavy load thrown on saidmotor after the same has been brought up to speed, the fluidpressure.,acting on the plston 44 will be reduced and the .pring48 willconsequently act toefi'ect an upward movement of the bridge piece 46,and thus re-insert some of the sections of the starting resistance 78,and thus protect the motor and increase its tor ue so that it may beagain brought up to all speed. The speed is, therefore, autofor varyingloads.

Instead of having the resistance 78 connected to the rotor, the same maybe connected to the stator circuits, so,that my invention may be used tocontrol the current supplied to the stator. Such an arrangement however,is preferable only when direct current motors are used, for in such casethe starting resistance could be placed in circuit with the armature andgradually cut out to effect a re-acceleration of the motor. My apparatusis also adapted to operate an adjustable transformer so as to vary thevoltage which is applied to the motor, and thereby regulate the speedthereof.

When the car switch S is moved to open position, the current to themotor will be interrupted, and so also the current through the brakemagnet. The brake spring 28 will thereupon act to apply the brake B tothe brake pulley P. It has been found in practice, that by reason of theheavy rotors of induction motors, the brakeapglying means could not beeasily made of cient strength to sto the motor in ashort space of time.I esire to adapt the ordinary brake-applying'means to thestopping of themotor, and have the fluid pressure apparatus cooperate therewith to stopthe motor gradually in a minimum space of time. When the current is cutoff from the motor, it still runs by momentum and operates the fiuidpressure apparatus A to, force the fluid through the pipe 68 to thecylinder 35. When the brake magnet is denergized, and the brake shoe Bapplied, the piston valve 34 will be moved to the left so that the fluidconfined above the piston 44 can escape atmosphere. The aperture 7 8tlirrg.

through the pipe 42 and thencearound the groove 38 through the aperture41 to the atmosphere. The spring 48 will therefore act to move thepiston 4A and bridge piece 46 to their original positions, and thusreinsert the resistance 78. If desired, the rate of upward movement maybe regulated by varying the sizes of'the apertures 41 and 47, but it ispreferable that the piston H should have a nearly free return movement,and retarded only to such an extent that it will be cushioned at theupper end of its movement. When the piston valve is left, the fluidpressure apparatus A, which is now being operated by the momentum drivenmotor M, will propel fluid under pressure through the pipe 68 into thecylinder 85, and thence through the passage 37 and port 37 through thegroove 36, and thence by way of pipe 77 to the cylinder 28 at the rightof the piston 30. Fluid pressure will therefore be exerted on the piston30 to assist the brake spring 28 in applying the brake shoe B to thebrake pulley P. It is evident that this extra braking action will beproportionate to the speed at which the motor M is rotated at the timethe brake inagnet is deenergized. The action'of the spring 28 ispractically constant and holds the motor shaft 7 6 stationary after themotor has been stopped. It should also be noticed that when the brakemagnet is deenergized and the fluid pressure apparatus A is operated bythe momentum driven motor M, the fluid within the cylinder 29 and thepipes connecting the same with the fluid actuator or propeller isgradually increased in pressure as there is no means for permitting thefluid to escape when the piston valve 34: is in the position shown. theefl'ect of further retarding or gradually stopping the rotor of themotor M, by reason of the gradually increasing action of the fluidpumped into the pipe 68. Further- 'more, when the motor is stopped,check valves between the air actuator A and the chamber 69 will confinethe fluid under pressure within the pipe 68, and consequently alsowithin the cylinder 29, thus assisting the spring 28 in holding thebrake shoe B in firm engagement with the brake pulley I. Heavier loadsmay thercar C and held in position without set- W'hen the brake magnetis again onerglzed, and the piston 34 drawn to the right, communicationwill be established between the pipe 77 and the cylinder 35 to the leftof the piston 34 so that the fluid under pressure within the cylinder 28may escape through said pipe 77 into the cylinder 35, and thence throughthe aperture 7 8 to the may be omit ted however, as the brake magnet maybe of suiiicient strength to act against both the spring 28 and theconfined fluid under pressure,

'rangement of parts,

thus moved to the.

This has therefore be carried by to release the brake magnet B and holdthe same released. In such case an elastic fluid such as air will bepreferable.

Obviously those skilled in the art may make various changes in thedetails and arwithout departing from the principles of my invention. Itherefore do not desire to be restricted or limited to the preciseconstruction herein shown and described.

What I claim and desire to have protected by Letters Patent of theUnited States, is:

1. In an elevator, the combination with a motor, of motor controllingapparatus, means for operating said motor controlling apparatus, valvemechanism for controlling said operating means, brake mechanismcontrolling said valve mechanism, a device operated by the motor foroperating said valve mechanism by fluid pressure, and means independentof the fluid pressure for restoring the valve mechanism to initialposition.

2. In an elevator, the combination with a motor, of means forcontrolling the speed of the motor, a valve for controlling saidspeed-controlling-means, a device operated by fluid pressure foractuating said valve, elect-ro-responsive valve restoring means, andbrake apparatus controlled by said electro-responsive means.

3. In an elevator, the combination with a motor, of fluid pressureapparatus substantially entirely automatic in operation and connected tothe motor, starting appliances for the motor, means operated by fluidpressure supplied by said apparatus for operating the startingappliances, mechanism for controlling the application of fluid pressureto said starting-operatingmeans, brake apparatus controlling saidmechanism', and means independent of the fluid pressure for restoringsaid controlling mechanism to initial position.

4. In an elevator, the combination with the piston connected to the partto be actuated, of a resilient device on one side of said piston, fluidpressure apparatus for effecting the movement of said piston, andpermitting fluid to escape to regulate the maximum pressure on saidpiston.

5. In an elevator, the combination with a piston connected with the partto be operated, of a spring for moving said piston in one direction,means for propelling fluid directly to said piston to move the same inanother direction, a valve in the path of said fluid and operable in onedirection by fluid pressure for connecting the su ply of fluid to saidpiston, and means in ependent of fluid pressure for actuating said valvein the reverse direction into position to block the flow of fluid tosaid piston.

6. In an elevator, the combination with an electric motor, ofaccelerating mechanism when the car is therefor, means for propellingfluid to actuate said accelerating mechanism in proportion to the speedof said motor, electric means for controlling the flow of fluid, andreversing switch mechanism for controlling the said electric means.

7. In an elevator, the combination with a motor, of a source of powerfor said motor, a fluid actuator operated by said motor, motoraccelerating means. means for directing a fluid from said fluid actuatorto operate said accelerating means, electron'iecluinical means forcontrolling the flow of fluid, and reversing switch mechanism forcontrolling said elect-r0-mechanical means.

8. In an elevator, the combination with a motor, of two sources ofpower, one being electric and substantially constant in value, the otherbeing fluid pressure and in strength proportionate to the speed of saidmotor; connections substantially all electrical to effect the operationof said motor by the electric power; means operated by fluid pressurefor effecting the acceleration of the motor, and elcctro-mechanicalmeans for controlling bot-h of'said powers.

S). In an elevator, the combination with an electric motor, of a fluidactuator driven only when said motor operates, starting switches forsaid motor, electric means for operating said starting switches, andmeansoperated by the fluid actuator for controlling the acceleration ofsaid motor.

10. In an elevator, the combination with a motor, of reversing switchestherefor, starting resistance for. said motor, fluid pressure apparatusconnected to be operated by said motor, means actuated by fluid pressurefor varying said resistance to regulate the speed of said motor, andelectro-mechanical means for controlling the application of fluidpressure to said resistance varying means. I

11. I11 an elevator, the combination with a car. of hoisting apparatustherefor, of a motor connected to drive said hoisting apparatus,fluid-ccnnpressing mechanism connected to the motor and driven therebyonly in motion, means operated by the compressed fluid for controllingthe acceleration ofsaid motor, a valve for controlling said means, andan electro-magnet for actuating said valve.

12. In an elevator, the combination with a car, of hoisting apparatustherefor, a. motor for driving said hoisting apparatus, two sources ofpower, one being electric and connected to the motor, and the otherbeing fluid and proportionate in strength to the speed of the car, meansoperated by said powers to effect the acceleration and operation. ofsaid motor and hoisting apparatus, and electric controlling means forsaid accelerating means.

13. In an elevator, the combination with a car and hoisting apparatustherefor, of a means for restoring said valve to normal position toeffect a restoration of said accelerating means.

14-1 In an elevator, the combination with a car, of hoisting apparatusand motor, of two soru-ces of power, one being electrical andsubstantially constant in value and adapted to start the motor, meanssubstantially all electrical for restoring the electric power, and theother power being fluid and proportionate in strength to the speed ofthe car, and means operated by said powers for controlling theacceleration of the motor.

15. In an elevator, the combination with a car and its hoistingapparatus, of a motor connected to said hoisting apparatus,fluidpropelling means connected to be driven only when the car is inmotion, electric means for controlling the starting and stopping of themotor from' the car, and means operated by the fluid from saidfluidpropelling means to control the acceleration of the car. 1

16. In an elevator, the combination with a car and its hoistingapparatus, of an alternating current motor connected to said hoistingapparatus, a fluid actuator connected to be driven by said motor. motoraccelerating means, means for operating said accelerating means, andelectrically controlled means for directing and controlling the fluidfrom said fluid actuator to effect theactuation of said motoraccelerating operating. means.

17. In an elevator, the combination of a car and moving means therefor,comprislng a motor, motor controlling means, a fluid actuator,operated-by the motor and operable to supply fluid pressure proportionalto the speed of the motor, and means con-. trolled electrically from thecar for controlling the application of fluid pressure to saidmotor-controlling means to effect a gradual increase of speed of saidmotor.

18. In an elevator, the combination wlth a car and hoisting apparatustherefor, of a motorfor driving said hoisting apparatus, a fluidactuator connected to be driven by said motor, motor-controlling means,means for directing and controlling the fluid from said fluid actuatorto said motor-controlling means, and electric means for effect-mg theoperation of said fluid-controlling means from the car.

- the speed of the car,

19. In an elevator, the combination with a motor, of fluid-propellingmeans operated thereby, of a controlling valve therefor, an acceleratingdevice for the motor, a piston connected to said device and arranged tobe moved by the propelled fluid, means controlled fi-rom the car foroperating said valve to open position, and means for automaticallyrestoring the said valve to normal position.

20. In an elevator, the combination with a car and hoisting apparatus,of the driving motor, motor-controlling means, fluid-pressure apparatusfor operating said means in proportion to the speed of the car, andautomatic means connected to the ear for controlling said fluid-pressureapparatus.-

21. In an elevator, the combination with a motor, of a fluid actuator,operable to supply fluid at a pressure proportional to the speed of themotor, motor controlling means, means for establishing communication between the fluid actuator and said motor controlling means, a valve forcontrolling the application of fluid pressure to operate said motorcontrolling means, an electro-responsive device for moving said valve tosupply position, and automatic means for moving said valve to exhaustposition.

22. In an elevator, the combination of a car and moving means therefor,comprising an electric motor, accelerating means for said motor, apiston connected to said accelerating means, a resilient device on oneside of said piston, fluid pressure apparatus for supplying fluidpressure proportional to the speed of the motor for eflecting themovement of said piston to operate said accelerating means, andelectro-mechanical means for controlling said fluid pressure apparatusfrom the car.

23. In an elevator, the combination with a car and its motor, ofaccelerating means for said motor, a piston connected to saidaccelerating means, a spring for moving said piston in one direction,fluid pressure apparatus for moving the piston in the opposite directionto positions corresponding to the speed of the motor, a valve forcontrolling the supply of fluid 'to act against said piston, and meanscontrolled -from the car for operating said-valve to open or close thesame.

24 In an elevator, the combination with a car, of hoisting apparatustherefor, of a motor connected to drive said hoisting apparatus,motor-controlling means, a fluid actuator depending upon the operationof said motor to effect the operation of said motor-controlling means inproportion to and means controlled from the car for operating the saidmotor fluid actuator and motor controlling means.

the car for operating 25. In an elevator, the combination with a car, ofhoisting apparatus therefor, of a drivingv motor, means for acceleratingsaid motor in a predetermined time, a fluid actuator dependent upon themotor for operating said accelerating means, a valve and anelect-ro-responsive device controlled from said valve.

26. In an elevator, the combination with a car and its motor, of meansfor regulating the speed of said motor, comprising a fluid actuatorconnected tosaid motor,an opposition element, and means for cutting outportions of said opposition element; a valve for controlling saidmotor-speed regulating means, and means for operating said valve fromthe car.

27 In an elevator, car and its motor, of accelerating apparatus for saidmotor, fluid propelling and controlling means supplying fluid pressurecorresponding to the speed of the motor for automatically operating saidaccelerating apparatus, means for controlling the application of fluidpressure to said accelerating apparatus, and means carried by the carfor electrically controlling said fluid-pressurecontrolliiigmeans.

28. In an elevator, the combination with an electric motor, of a fluidactuator connected thereto, a brake, and electro-mechanical means fordirecting and controlling the flow of fluid to effect the application ofsaid brake.

25). In an elevator, the combination with a motor, of a fluid actuator,a brake pulley on the motor shaft, a brake shoe associated with saidpulley, a piston connected directly to said brake shoe, and means fordirecting and controlling the fluid from said fluid actuator to act onsaid piston to apply the brake.

30. In an elevator, the combination with a motor, of a fluid compressor,brake mechanism, means for applying said brake mechanism, and means fordirecting and controlling the fluid from said compressor to effect anadditional. actuation of said brake.

31. In an elevator, the combination with an induction motor, of a brake,bralrercleasing means, brakeaipplying means, a fluid actuator, and meansactuated by fluid from said fluid actuator to assist the brakcapplyingmeans to apply said brake to retard or stop said motor.

In an elevator, the combination with an induction motor, of a fluidcompressor,

b 'ake, means for applying said brake, and means for controlling anddirecting the fluid.

from said fluid actuator to effect an additional actuation of saidbrake.

33. In an elevator, the combination with an induction motor of a fluidactuator, a brake, brake-applying means, an elcc roresponsive device forreleasing said brake,

motor, and an electro-responsive device, for

releasing said brake.

35. In an elevator, the combination with a car and hoisting apparatustherefor, an induction motor, a fluid compressor connected to be drivenby said motor, starting and accelerating means connected to said motor,a brake, brake applying means, a valve,'an electro-responsive device forreleasing said brake, and moving said valve to effect the operation ofsaid starting and ac-' celerating means by fluid pressure, and meansco-acting with said valve for d recting the fluid under pressure fromsaid fluid compressor to assist said brake applying means in stoppingthe motor.

36. In an elevator, the combination witha motor, of a fluid compressoroperated thereby, starting and accelerating means for said motor, meansfor controlling the application of fluid pressure to said startin andaccelerating means, a brake, brdl e-applying means, and means co-actingwith said controlling means for exerting an additional braking action byfluid pressure in proportion to the speed of said motor.

37. The combination with an alternating current motor, of alternatingcurrent electro-magnetic reversing switches therefor, accelerating meansfor said motor, and a fluid-actuator for operating said acceleratingmeans. I

38. The combination with an electric motor, of reversing switchestherefor, normally held in open position accelerating mechanism andmeans for operating the same, electric means for closing said switches,fluid pressure, and mechanism for automatically effecting the operationof said accelerating mechanism.

39. In an elevator, the combination with a driving motor, ofaccelerating apparatus therefor, a piston connected to said acceleratingapparatus, a spring acting upon one side of the piston to move the samein one direction, fluid-pressure apparatus acting upon the other sideonly for moving the piston inthe opposite direction, a valve forcontrolling the supply of fluid to act against said piston, and meanscontrolled from the elevator for operating said valve.

40. In an electric elevator, the combination with an alternating currentmotor, of alternating current electro-magnetic starting switchestherefor, accelerating means for said motor, and a fluid-actuatingdevice connected to the motor for operating said accelerating means.

41. The combination with a motor, of an acceleratin device for themotor, means operated by uid pressure for controlling said device, abrake pulley, an electromagnet having a movable core, a brake shoeconnected to the magnet core, a valve connected to 'said core andcontrolling said fluid pressure, and means for controlling theelectromagnet. a

42. The combination with an electric motor,'of a starting resistance forthe motor, a device operated by fluid pressure for controlling saidresistance, means for supplying fluid pressure to said device, anelectromagnet and controlling means therefor, said magnet comprising amovable core, a brake pulley for the motor, a brake shoe connected tothe magnet core, and a valve connected to said core and controlling thesupply of fluid pressure to the resistance-controlling-device.

In testimony whereof, I have signed my name to this specification in thepresence of two subscribing witnesses.

AUGUST SUN DH.

